Firefighters are exposed to carcinogens and have elevated cancer rates. A new study led by researchers at the University of Arizona Mel and Enid Zuckerman College of Public Health examines occupational exposures to carcinogens in firefighters would lead to DNA methylation changes associated with activation of cancer pathways and increased cancer risk. The study was published in the journal PLOS One on March 26.
The researchers collected peripheral blood samples from 45 incumbent and 41 new recruit non-smoking male firefighters and analyzed the samples for DNA methylation using an Illumina Methylation EPIC 850k chip. Adjusting for age and ethnicity, they performed a genome-wide differential methylation analysis; a genome-wide prediction for firefighter status and years of service; and Ingenuity® Pathway Analysis (IPA). Four CpGs, including three in the YIPF6, MPST, and PCED1B genes, demonstrated above 1.5-fold statistically significant differential methylation after Bonferroni correction.
Genome-wide methylation predicted with high accuracy incumbent and new recruit status as well as years of service among incumbent firefighters. Using IPA, the top pathways with more than 5 gene members annotated from differentially methylated probes included Sirtuin signaling pathway, p53 signaling, and 5′ AMP-activated protein kinase (AMPK) signaling.
These DNA methylation findings suggest potential cellular mechanisms associated with increased cancer risk in firefighters.Tags: Friday Letter Submission